Peel the pears, leaving the stalks intact. Quarter the fruit lengthways and remove the cores. Place the pear quarters in a deep pan with the sugar and cover with the water. Gently bring to the boil, then cover with damp greaseproof paper (the paper should touch the fruit) and reduce the heat. Simmer for 3 minutes until the pears are tender. Drain and cool quickly in iced water. Meanwhile, pre-heat the grill to high. Cut the mozzarella into 24 long thick fingers and wrap each in a small piece of Parma Ham. Place on a foil lined tray and grill for 3-4 minutes until the cheese is golden. In a small bowl mix together the butter and parmesan cheese. Spread over the parma ham. Grill for 5 minutes. Place 2 pear quarters on each serving plate. Add some of the radicchio to each, then top with the grilled mozzarella. Drizzle with a little olive oil and lemon juice and add a grinding of freshly ground black pepper. Serve immediately.